Influenza: Diagnosis and Management (Pediatric Nursing)

00:01 So, how do we diagnose influenza? Well, there are so many patients who end up with influenza each flu season that we don't run diagnostic tests on everyone.

00:11 Typically, the diagnosis of influenza can be made clinically, based on the patient's history and the physical exam findings.

00:19 If you do need to run a diagnostic test on your patient, there are different approaches.

00:23 They're not always indicated, they're not always cost-effective, and they may not help you actually manage your patient.

00:30 So, most patients demonstrating clinical symptoms consistent with uncomplicated influenza and living in an area with a local outbreak do not require influenza testing.

00:40 So there are pros and cons to testing, and what are these? You've got to think about the cost.

00:44 You have to think about the pain of the procedure, and you have to think about the duration and how long this test is actually going to take to get the results.

00:51 The most commonly used test is a nasal pharyngeal swab called the rapid influenza test.

00:56 This test can provide results in about 15-20 minutes.

00:58 However, the results vary, and they're not always accurate.

01:02 Prior to testing your patient, the clinician should assess a pre-test probability.

01:07 This will decrease the likelihood that you have a false positive or a false negative screening.

01:14 Here's a good diagnostic tree.

01:15 First, the clinician needs to decide, does your patient have clinical signs and symptoms compatible with influenza? If it's "Yes," you can proceed down the algorithm.

01:25 Now you have to decide, will the results of your test change your clinical care of your patient? Well, they might in a patient who's hospitalized, or a patient with a high-risk condition, because these are the patients in which antivirals are recommended.

01:40 You have to also think, "Will this influence clinical practice for other patients, such as family members or cohorting your patients in the hospital?" And you have to think, "Will you initiate antiviral treatment if clinically indicated based on the results?" If this doesn't change your diagnostics, you would stop here, but if so, you would start your antiviral treatment prior to the results from your diagnostic tests.

02:05 "Yes," consider influenza testing in your patient.

02:08 And then you're going to interpret the results.

02:11 If your patient does not display signs and symptoms of influenza when they present to the clinic, you would probably not do a flu test on these patients.

02:19 And if you wouldn't change your treatment, if you wouldn't need to cohort your patients, and if it wouldn't change the clinical care of that patient, then also an influenza viral testing is probably not indicated.

02:32 Here are some diagnostic options.

02:34 First, is the viral culture.

02:36 This has a moderately high sensitivity and the highest specificity available.

02:41 It's good to confirm influenza in your patients.

02:44 It's useful in public health surveillance, but it's not recommended for timely clinical management because you won't get these results for 2-3 days.

02:54 Another option is a PCR test.

02:56 This is the most sensitive and specific test that we have available for influenza testing.

03:01 It can also be used to confirm influenza in your patients.

03:05 It can quickly differentiate between influenza types and subtypes, and you'll get these results in about 4-6 hours.

03:12 Another option in the outpatient setting is a rapid influenza diagnostic test.

03:17 This is a screening test.

03:18 You'll get results in about 15-30 minutes.

03:21 Now, this is a good test for ruling in influenza.

03:24 It has a very high specificity of about 90%-95%, but the sensitivity isn't that great, about 50%-70%.

03:32 So you will miss influenza in about 30%-50% of your patients.

03:38 Immunofluorescence is another option, and this has a lower sensitivity and specificity than the viral cell culture and this is also a screening test.

03:46 You can get the results in 3-4 hours.

03:50 How do you manage a patient with influenza? Well, typically, the patient will have a self-limiting course.

03:56 They won't need anything more than time, rest, and plenty of fluids.

04:02 A patient can take antipyretics to bring down their fever, but this is always an interesting talking point with your patients.

04:09 So, what is a fever doing? A fever is helping activate certain immune cells that help fight the virus.

04:17 So, when a patient treats their fever, they're actually decreasing the ability of those immune cells to fight the virus.

04:23 So, patients are afraid of fevers.

04:25 I found that in the clinic.

04:26 I'll ask, "Why are you afraid of this fever?" And they'll say, "Because it's- I have a fever." And they can't really explain, and I explain to them, the fever is helping them.

04:33 So, as long as they can stay hydrated, as long as they can drink fluids and tolerate their fever, they can have a fever.

04:41 It's easy for a patient to be dehydrated when they have influenza.

04:45 They may have lost their appetite.

04:46 Maybe they're laying in their bed sleeping for a large portion of the day.

04:50 And then also their fever, with their increased respiratory rate, is going to further dehydrate them.

04:55 So, encourage your patient.

04:56 They might not be hungry.

04:58 That's okay.

04:58 They don't need to eat for even a few days, but they do need to keep up on their fluids.

05:04 In some cases in high-risk patients who present early on in their illness, antivirals, such as Tamiflu or Relenza, will be prescribed.

05:12 And these drugs don't really do much once the patient is already sick.

05:16 Let's say they're going to be sick for 10 days with influenza.

05:19 It makes it so they're going to be sick for 9 days with influenza.

05:22 But they are less likely to die from their influenza, if they do take the antivirals.

05:26 Now, the antivirals don't do anything to take away the virus that's already circulating in the body, but they will inhibit more of that virus from being released.

05:35 There are side effects to the medications and patients should be counseled about these, and they need to weigh the benefits and the risks.

05:42 Some common side effects include nausea and vomiting, and they can be lessened if the drug is taken with food.

05:48 Now, Tamiflu has also been associated with delirium and self-harm behavior in teenagers.

05:55 The patient's going to need to stay out of the community because this is a very contagious virus, until they're fever free for 24 hours without needing medications to bring it down.